Most of the barriers for Alpha adoption were problems inherent in the 32-bit to 64-bit transition. Alignment problems, yes, but another killer problem was that 64-bit pointers were twice as large.

The software I was writing at the time (EDA) took almost exactly twice as much memory. So if we needed more than 4GB, we could go to a 64-bit machine, but unless you bought even more than 8GB, you couldn't really run on bigger problems.

As you note, all those problems had to be sorted out 10 years later, when AMD finally forced Intel's hand into selling 64-bit computers.